The present proposal describes a series of planning activities to develop an international collaborative program of research on cognitive and brain phenotypes of mentally retarded Chinese children with genetic disorders. Specifically, an international team of medical, psychological, genetic, and computational researchers from P.R. China, the United Kingdom, the United States, and Canada will collaborate to study Chinese children with Fragile-X syndrome (FXS), Williams syndrome (WS), and Down syndrome (DS). The specific aims of the present research planning proposal are:(1) To assess the existing research infrastructure at the Chinese institution (Zhejiang University) for conducting the proposed research activities, (2) To enhance the research capacities of our Chinese research team through workshops and short-term training; (3) To conduct pilot studies that (a) test the feasibility of a computer-assisted 3D photography-based system for identifying a large population of mentally retarded children whose facial dysmorphology may suggest FXS, WS or DS and verify such identifications by genetic tests, (b) translate, adapt, and pilot-test procedures developed by the researchers in UK, US, and Canada to assess children with genetic disorders in terms of their abilities in the areas of language, executive function, and faces and visual-spatial information processing, and compare the Chinese children's cognitive profiles with the existing profiles of affected Western children; (c) use event-related potential techniques to examine the neuro-physiological correlates of a small group of the Chinese children with WS, FXS, and DS when they process language and face-spatial information, and compare the results with those obtained with the existing samples of affected Western children. Based on the outcome of 1,2, and 3, the international interdisciplinary team will develop a R01 research proposal that will systematically examine cognitive and brain functions or dysfunctions of Chinese children with Williams, Fragile-X, and Down syndromes from infancy to middle childhood. Our long-term goal is to chart the developmental trajectories of cognitive and brain development in children with genetic disorders, to understand the interaction between genetic abnormality and neuro-cognitive development in different socio-cultural contexts, and to provide information for the creation of syndrome-specific and, if necessary, culture-specific intervention programs.